A known apparatus of this kind is described in the following with reference to the attached FIG. 3. It comprises overhead hoppers 15, 16, 17 and 18, into which is transferred the flour from the mill's silos (not shown) prior to loading into a vehicle 29. From the hoppers 15-18 the flour passes through gates 14 attached to each of the hoppers 15-18, into a first (chain trough) conveyor 22 and thence into a second (chain trough) conveyor 23, which is displaceable (from left to right in FIG. 3). The conveyor 23 is equipped at each of its two ends with a filler nozzle 10 or 11, and is so constructed that it can convey the flour either to the nozzle 10 (on the right in FIG. 3) or to the nozzle 11 (on the left in FIG. 3). Below the arrangement just described, in particular substantially centered below the connection point of the first conveyor 22, is a weighing assembly 40 to provide a means of weighing vehicles, onto the bridge 47 of which the vehicle 29 can be placed. The bridge 47 rests on weighing cells 48 that are seated on a foundation 50.
The vehicle 29 comprises tank input openings 30-36, through which tanks 37, 38 of the vehicle 29 can be filled. The tanks 37, 38 can be subdivided into individual compartments, sealed off from one another, in which case each input opening 30-36 is associated with a single compartment.
The first step in filling is that the nozzle 10 or the nozzle 11 is firmly connected to one of the input openings 30-36 of the vehicle 29 by appropriately shifting the second conveyor 23 and lowering the nozzle 10 or 11. Then at least one of the gates 14 of one of the hoppers 15-18 is opened and the associated first conveyor 22 is put into operation, as well as the second conveyor 23 (being moved in the appropriate direction). Hence the flour can pass into the tanks 37, 38 of the vehicle 29. During the filling process the load is measured by the weighing assembly 40. In order for a predetermined amount of flour to be put into the tanks 37, 38 of the vehicle 29, the previously opened gate 14 must be shut at just the right time, so that the amount of flour in the entire passageway from the gate 14 to the filling nozzle 10 or 11 corresponds precisely to the difference between the actual content of the tank and the desired "control" content. This precision is made particularly difficult to achieve by the fact that the distance through the second conveyor 23 depends on whether the nozzle 10 or 11 is being used and to which of the tank openings 30-36 it is coupled; that is, the conveyor can contain various amounts in transport. Furthermore, this differential amount depends on the rate of transport of the conveyors 22, 23, so that good reproducibility of the results requires extremely precise transport velocity. These criteria are very hard to meet, especially in combination, with the result that the content of the tanks is seldom exactly as intended.
An additional problem in the known flour-loading apparatus is that the conveyors, in particular, are constructed with very many angles and corners to which access is difficult. In such angles and corners animal pests can shelter or develop, whereupon they continually contaminate the flour. At the same time, physical contaminants (foreign bodies, abrasion detritus) are unavoidably introduced by the known flour-loading apparatus.
Along with all these difficulties, the time required to load a vehicle must be made as short as possible so that a given flour-loading apparatus can load as many vehicles as possible per day; to handle the output of a large mill, it is often necessary for several flour loaders to operate simultaneously.